Black nylon plastic with a matte finish and slight grainy feel.
About this Product
Using this back plate adapter for the GraftConcepts (http://www.graftconcepts.com) Leverage i5 iPhone case you can now mount your phone to a Garmin ball mount anywhere you like.
I use it for GPS navigation on the streets and GPS lap timing/video on the track.
Metal retention ring from Garmin mount required for tight fit. Can be purchased from eBay for $10 or less.